Abstract Research Project 1 of the proposed Center for Latino Health Research Opportunities (CLaRO) is titled HoMBRES de Familia (Hispanic Men Building Respect, Education, and Safety within Families /Hombres Manteniendo Respeto, Educacion y Seguridad de Familia). The overall objective of this project is to adapt and enhance HoMBReS, a CDC-identified best-evidence HIV behavioral intervention designed to reduce substance abuse, family violence, and HIV/AIDS (SAVA) among sexually active heterosexual Latino seasonal farmworkers (LSFWs) in rural areas. Research Project 1 is integrated with the Center through a common set of measures and research questions on the syndemic approach. This application leverages the success of the originating Centers of Excellence and considerable institutional resources and support and community partnerships. The Lead of this project is an early career investigator who is an Assistant Professor associated with CRUSADA. Building on the work of El Centro and CRUSADA over the last decade, HoMBRES de Familia will utilize a community-based participatory research (CBPR) approach to develop and test a gender and culturally tailored intervention to prevent SAVA conditions in a vulnerable and underserved Latino population. The proposed interdisciplinary study will innovatively expand the SAVA syndemic paradigm by testing its etiologic theory through a carefully designed prevention trial. We will examine theorized risk and protective factors influencing the SAVA conditions among a never-before examined population (male LSFWs), demonstrate that these factors are malleable, and that changes in these mechanisms can impact SAVA outcomes. A two-arm randomized control trial will be conducted to examine the efficacy of the adapted intervention with a sample of 160 father-son dyads (N=320). The proposed mixed-methods study will be accomplished through the following Specific Aims: (1) Conduct a community assessment via qualitative data methods (in-depth interviews; focus groups) that will inform the adaptation of an evidence-based intervention targeting the SAVA syndemic among adult and adolescent males in the Latino seasonal farmworker community; (2) Adapt, implement, and evaluate the preliminary efficacy of the adapted intervention; and (3) In combination with the Community Engagement and Dissemination Core, develop an effective dissemination plan that engages community members, partnering organizations, local service providers, and other stakeholders in disseminating study findings into a sustainable intervention that effectively reduces SAVA- related health disparities among males in the LSFW community. Miami-Dade County has the highest rate of HIV/AIDS in the country and high rates of substance abuse and violence. LSFWs face disproportionate rates of SAVA conditions, and Miami-Dade County has one of the largest populations of LSFWs in the nation; this site is the ideal testing laboratory for the proposed Research Project.